Improvement in burglar-alarms



I A. G. H U T C H I N S 0 N & G. F. R A N S 0 M. B'URGLAR-ALARMS No.195,822. Patented 0ct.2,18'77.

V I L 1 34 TNESSE v v INVENTOR N.PETERS, PHOTO-LITHOGRAPHER. wAsnmsTou 0C UNITED STATES PATENT OFFICE.

ARTHUR G. HUTOHINSON AND GEORGE F. RANSOW, OF CLEVELAND, OHIO.

IMPROVEMENT IN BU RGLAR-ALARMS.

Specification forming part of Letters Patent No. 195,822, dated October2, 1877; application filed September 6, 1877.

a as will enable others skilled in the art to which it pertains to makeand use it, reference being had to the accompanying drawings, which formpart of this specification.

Our invention relates to a new and useful improvement in burglar-alarms;and consists in a tubular shell or case containing a plunger and aspring to actuate the same, and to the plunger is attached atrigger-arm, which moves in a right-angular slot; and the constructionis such that when the trigger-arm is set in the horizontal branch of theslot and the door is opened it will press the trigger into the verticalor longitudinal arm of the slot, and the spring will then force theplunger down against a friction or fulminate pad, or against a shieldcontaining the pad or pellet, thus exploding the same, and creating amarked alarm or report sufficient to arouse the occupants of the houseor apartment.

In the drawings Figure 1 represents one of our improved burglar-alarmsset ready for use. Fig. 2 represents the same after the door has beensufficiently opened to release the trigger. Fig. 3 represents the sameas applied to a window. Fig. 4. represents a variation, wherein theplunger is permitted to strike directly upon the fulminate-pellet. Fig.5 presents a variation of our invention, wherein the construction issuch that the trigger may be set during the day, and, when desired foruse, it may be engaged with a separate latch or catch.

A is a cylindrical or other case for containing a plunger or exploder,B, and O is a spring for driving the said exploder B. D is an arm ortrigger projecting outward from the plunger B, to which it is rigidlyattached, so that the motion of the plunger is governed by the motion ofthe trigger. E is the vertical arm, and E the horizontal arm, of arectangular slot. E is a short elongation of the slot upon the oppositeside of the vertical portion E, and E is a branch of the slot whichpermits a free movement of the trigger-arm after the device has beensprung or when not in use. F is a support or abutment, upon which thepellet of fulminate rests and is exploded. G is a small plate of metal,which serves to hold the pellet in place. This plate G is looselypivoted at g, so that, as the plunger strikes it, it will have aslightly rasping or sliding motion upon the friction-pad which is placedbetween it and the support F. This is not absolutely essential, however,as the plate may be dispensed with entirely, and the plunger bepermitted to strike directly upon the fulminate; or, instead of theplate G, a spring or retainer of any de scription may be employed forholding the pellet in place. We prefer, however, to employ the plate G,as shown.

H is the door-jamb, and H the door. H and H are, respectively, the upperand lower sashes of the window.

The operation of this device is very simple. Having secured the deviceto a door-frame, as shown, and the door having been closed, as shown inFig. 1, the alarm is set by lifting the trigger-arm l), and with it theplunger B, until the arm 1) rests within the horizontal portion E of theslot, and imtil the end of the trigger-arm rests against the door. Afulmi- 11ate-pad, G, is then placed beneath the plate G, and allisready.

Now, should a person open the door, the door will press upon the arm ortrigger D, and turn it until it is released from the portion E of theslot, and is driven down through the vertical portion E of the slot.Being attached to the plunger B, the spring 0 forces the plunger sostrongly as to explode the fulminate-pellet, thus creating a loud alarmor report. Having reached the bottom of the slot E, the arm D is thenfree to move in the branch E of the slot until again set.

If, for any purpose, it should be desired to give an alarm on theoccasion of an open door being closed, then the trigger-arm may be setin the slot E and be so attached to the door as to pull it free as thedoor closes.

It may at times be desirable to so construct the device that, althoughthe trigger D may be set, the door may still be opened and closedwithout springing the alarm. For this purpose the trigger-arm may bemade short, as shown in Fig. 5, so as not to be struck directly by thedoor; and when it is desired to guard the door a latch, I, may beengaged, as shown, with the arm D, so as to trip the trigger as the dooris opened.

It is not absolutely essential that the spring C and plunger B beincased in a shell, A, for it is apparent that the plunger and thespring might be arranged concentrically around a central supporting-stemwithout departing from our invention. 7

When it is desired to use the device upon a window, the apparatus is soattached that the raising or lowering of either frame or sash will tripthe trigger I), as shown in the drawings.

A device of this nature is simple and cheap, and furnishes a ready meansof attachment wherever it may be needed, and, with a couple of tacks ornails for fastening it, may be secured, in a few moments, to thewindowsand doors of a hotel apartment or other place where a portablealarm is needed.

It will be understood that instead of a pellet, as shown, beingemployed, we may use a cap or any other explosive agent which may beexploded with a blow of the plunger.

The branch E of the slot enables the device to be set, as beforeexplained, so as to trip the trigger as the door is swung away from theimplement. It is apparent that this may be employed to advantage insecuring doors which open outward from an apartment, which is frequentlythe case.

What we claim is- 1. A burglar-alarm consisting of the slotted shell A,plunger B, and coiled spring (J, the latter having butt end bearing,respectively, against the plunger and the close top of the shell, incombination with the buttress F formed independent of, and in ahorizontal plane below, the shell A, substantially as described.

22. The combination, with the upright cylindrical casing A and thespring-actuated plunger B, adapted to operate therein, as described, ofthe buttress or support F and the closebodied guard G, the said buttressand guard being located in a horizontal plane below the said casing A,substantially as described.

3. In a burglar-alarm, the longitudinallyslotted shell or casingprovided with the lower cross-slot E the latter being adapted, asdescribed, to receive the triggerarm when the alarm is not set, and thuspermit the opening and closing of the door without injury to theoperative parts of the alarm, substantially as described.

4. In a burglar-alarm, the combination, with the spring-actuated plungerhaving a triggerarm, of the longitudinally slotted shell provided withthe crossslot E and suitable doorconnect-ing mechanism, the same beingadapted, as described, to operate the alarm upon closure of the opendoor, substantially as de-

